METHOD OF CLEANING GASES FROM HYDROGEN FLUORIDE AND SULFUR DIOXIDE Russian patent published in 1997 - IPC

FIELD: gas scrubbing from acid components; may be used in cleaning gases, particularly, furnace gases of cryolite production, gases formed in melting fluxes, glass crumbs and special glass. SUBSTANCE: gases are cleaned by their cooling and dust separation, scrubbing with water in counterflow in the cascade of successively installed absorbers with production of hydrofluoric acid with subsequent supply of gas for cleaning from hydrogen fluoride into absorber where absorber is used in the form of service water in the amount of 1 liter for 80-160 liters of gas. Used water is used as absorber at the stage of production of hydrofluoric acid, and gas is treated with 5-10%-solution of sodium carbonate in the amount of 1 liter of solution for 520-1000 liters of cleaned gas. Used solution is regenerated by the known methods. Cleaning efficiency from hydrogen fluoride is 92-99% and that of sulfur dioxide is 95-99%. EFFECT: highly efficient and selective cleaning of effluent gases, cut down of the process due to reduced consumption of reagents and obtaining regenerated used solution. 2 tbl